Refrigerator

ABSTRACT

A refrigerator includes a condenser which is connected into a refrigerating circuit and embodied as a tubular heat exchanger having tube sections. At least one heat accumulator element is inserted into an installation interspace between the tube sections of the condenser. The heat accumulator element is arranged in spaced apart relationship to the tube sections of the condenser by at least one predefined air flow gap.

The invention relates to a refrigerator according to the preamble ofclaim 1.

Refrigerators have a condenser connected in a refrigerating circuit. Thecondenser is a heat exchanger by means of which the heat absorbed in therefrigeration process is released outside of the refrigerator to theambient air. Different designs of condensers are used for this purpose:With statically ventilated condensers, the surface area is enlarged toprovide better heat dissipation by means of sheet metal strips or wirearrays which connect the heat exchanger tubes to one another. Thestatically ventilated condenser is mounted on the rear of therefrigerator. Alternatively thereto, there are forced-ventilationcondensers which can be implemented with significantly smallerdimensions. A separate fan can be arranged between the condenser and acompressor for the purpose of dissipating the heat from the condenser bymeans of its air flow.

DE 20 2006 007 585 U1 discloses a generic refrigerator in which thecondenser is embodied as a tubular heat exchanger with a tube coil whichhas horizontally running linear tube sections which are interconnectedvia edge-side tube bends. In order to increase the efficiency of therefrigerating circuit the generic refrigerator has a latent heataccumulator which absorbs heat given off by the condenser. A change inthe aggregate state takes place when the heat given off by the condenseris absorbed. The aggregate state is reversed again during a standstilltime of the refrigerating circuit by dissipation of heat to theenvironment.

In the generic refrigerator the latent heat accumulator is in directcontact with the condenser tubes. In this way a direct thermaltransition is provided from the condenser into the latent heataccumulator.

The object of the invention is to provide a refrigerator in which therefrigerating capacity of the refrigerating circuit is increased bysimple means.

The object is achieved by means of the features of claim 1. Advantageousdevelopments of the invention are disclosed in the dependent claims.

The invention is based on the knowledge that free flow cross-sectionsbetween the heat accumulator element and the condenser's middle tubesections, which run in particular horizontally and in a straight line,enable faster heat dissipation from the condenser. Contrary to the priorart, therefore, the heat accumulator element according to the inventionis spaced apart from the tube sections of the condenser by at least onepredefined air flow gap. In this way an additional natural convectiontakes place in the air flow gap obtained, thus assisting in acceleratingthe heat dissipation from the condenser.

In order to provide more effective heat dissipation the surface area ofthe condenser can be enlarged by means of cooling structures. Suchcooling structures can be provided on the front side and/or rear side onthe tube coil of the condenser in the form of wire arrays. Alternativelythe condenser surface area can be increased in size by means of sheetmetal strips which interconnect the tube sections. The front andrear-side cooling structures, together with the tube sections of thecondenser, in each case delimit installation interspaces in which theheat accumulator element can be inserted. According to the invention theheat accumulator element can in this case be arranged contactlessly, inparticular roughly centrally, between two neighboring tube sections. Inthis way the heat accumulator element is spaced apart by the same gapdimensions from the upper and lower tube sections. The heat accumulatorelement can be designed in roughly a strip shape.

A permanently correctly positioned arrangement of the heat accumulatorelement in the installation interspace between the neighboring condensertube sections is imperative. For this purpose an additional retainingelement can be provided in the respective installation interspace inorder to ensure positionally secure retention of the heat accumulatorelement. The retaining element can be in particular a retaining wirewhich is supported on the heat accumulator element in the installationinterspace. The retaining element can be embodied on the front and/orrear cooling structure, in particular secured thereto by means of awelded joint.

Alternatively or in addition the heat accumulator element can be fixedlyclamped inside the installation interspace between the front and rearcooling structures by means of a simple clamp connection.

As mentioned above, the cooling structure of the condenser can beimplemented as a front and rear wire array. In this case the heataccumulator element is installed by insertion into the laterally openinstallation interspace between neighboring condenser tube sections. Asthe heat accumulator is inserted into the installation interspace thefront and rear wires of the cooling structure bend apart in anelastically resilient manner, as a result of which the inserted heataccumulator element is securely held by the clamping forces applied bythe wire arrays.

As already mentioned above, free flow cross-sections between the middlecondenser tube sections running in a straight line are extremelyimportant for effective transfer of the heat from the condenser to theenvironment. Against this background, a heat accumulator element can bearranged alternatively or in addition on the edge side in the region ofthe outer tube bends of the condenser. In this way the installationinterspaces between the horizontally running linear tube sections canremain completely free in order to increase the flow conditions, whileonly the outer condenser tube bends on the edge side can be thermallycoupled to the heat accumulator element.

Heat accumulator elements can preferably be provided on opposite edgesides of the condenser in each case such that they can extend in themanner of frame strips along the edge sides of the condenser.

To provide simple retention on the condenser, the heat accumulatorelement can be threaded through the horizontally running condenser tubesections in a meandering shape at a roughly right-angled orientationwith respect to said tube sections. In this arrangement the heataccumulator element can be folded on the end side in the manner of aloop around a tube section of the condenser and secured.

It is particularly preferred for effective heat dissipation from thecondenser if the edge-side heat accumulator elements are embodied in theappliance side direction outside of the front and/or rear condensercooling structures. In this way the heat accumulator elements arearranged in the appliance side direction so as not to be overlappingwith the cooling structure. An adverse effect on the mode of operationof the cooling structure due to overlapping heat accumulator elementscan therefore be avoided.

As described above, the heat accumulator element can be routed in ameandering shape and roughly at right angles through the condenser tubesections in order to be retained on the condenser. Alternatively hereto,the heat accumulator element can be mounted on the outside onto theouter tube bends of the condenser. To provide a positive-lockingconnection the heat accumulator element can have at least one recessinto which a tube bend of the condenser can project.

Alternatively thereto, the heat accumulator element can be a roughlyU-shaped hollow profile part into the cavity of which tube bends of thecondenser can project. In this case the heat accumulator element can beembodied by way of example as an elongate extruded part, that is to sayin material measured by the yard which is favorable for manufacturingprocesses. The hollow profile part mounted onto the condenser on theedge side can enclose the outer tube bends of the condenser in themanner of a cover.

The present invention can be used both for statically ventilatedcondensers and for forced-ventilation condensers. In the case of such aforced ventilation the condenser is assigned a separate fan whichgenerates an air flow through the condenser in order to dissipate thecondenser's heat. In this case the condenser can be arranged in acooling air duct which is partly delimited by at least one heataccumulator element. Preferably the heat accumulator elements can beembodied as cooling air duct sidewalls between which the condenser isarranged. The heat accumulator elements can therefore take on a dualfunction, additionally being used as air guide parts.

In order to increase heat dissipation from the condenser, the heataccumulator element can have a material which changes its aggregatestate upon absorbing heat given off in the refrigeration process. Thechange in aggregate state is reversed again during a standstill time ofthe refrigerating circuit through dissipation of heat to theenvironment. The material can be by way of example a material fixed in amatrix and having the same mechanical properties irrespective of theactual temperature. In this case the relevant transition point for thechange in the aggregate state can be warmer than the typical ambienttemperatures or the temperatures defined in the standards for measuringthe energy consumption of refrigerators. By this means it is ensuredthat the heat accumulator element is cooled down again below thetransition point during the refrigerating circuit standstill time. Withdynamically ventilated condensers, the fan can be activated during therefrigerating circuit standstill time, as a result of which thecondenser can be effectively cooled overall.

Three exemplary embodiments of the invention are described below withreference to the attached figures, in which:

FIG. 1 shows in a perspective view from behind a refrigerator having acondenser with partially inserted heat accumulator element according tothe first exemplary embodiment;

FIG. 2 shows the heat accumulator element inserted into the condenser inan enlarged sectional view along the section plane I-I;

FIG. 3 shows a view corresponding to FIG. 2 according to a variation;

FIG. 4 shows a view corresponding to FIG. 2 according to a furthervariation;

FIG. 5 shows an arrangement of the heat accumulator element on thecondenser according to the second exemplary embodiment;

FIG. 6 shows the heat accumulator element according to the secondexemplary embodiment in a variation; and

FIG. 7 shows a forced-ventilation condenser provided with heataccumulator elements according to the third exemplary embodiment.

FIG. 1 shows in a partial view from behind a refrigerator 1 having acondenser 3 mounted on the rear wall of the housing. The condenser 3 isventilated statically and has a tube coil running in a meander shape andhaving horizontal, linear tube sections 5 which are arranged spacedapart from one another in a vertical plane one above the other. Themiddle tube sections 5 according to FIG. 1 are connected to one anothervia lateral tube bends 6.

As front and rear cooling structures, the condenser 3 has wire arrays 7,9 which increase the size of the condenser surface area in order toprovide more effective heat dissipation. FIG. 2 shows a detail of thecondenser in a sectional side view. According thereto, wires of thefront and rear wire arrays 7, 9 are fixed to the respective condensertube sections 5 via connecting points 11. Together with the wire arrays7, 9, the neighboring tube sections 5 shown in FIG. 2 form aninstallation interspace 13, open in the appliance side direction in eachcase, into which can be inserted, according to FIG. 1, a heataccumulator element 15 embodied in this case by way of example asstrip-shaped. The heat accumulator element can be by way of example anelongate pouch filled with a material, wherein the material can changeits aggregate state upon absorbing heat given off by the condenser inthe refrigeration process.

As shown in FIG. 2, the strip-shaped heat accumulator element 15 isspaced apart from the upper and lower condenser tube sections 5 in acontactless manner via air flow gaps 17. Contrary to the prior art,therefore, there is no direct contact with the condenser tube sections5. Rather, flow conditions in the region of the condenser 3 can beimproved with the aid of the air flow gaps 17 to the extent that theefficiency of the heat dissipation from the condenser 3 is increased.

For stable retention of the heat accumulator element 15, the wire pieces19 shown in FIG. 3 can be provided inside the installation interspace 13as retaining elements which are fixed for example by way of a weldedjoint to the front and rear wire arrays 7, 9. According to FIG. 3, theheat accumulator element 15 is reliably as well as permanently supportedon the two wire pieces 19.

Alternatively to FIG. 3, the width of the heat accumulator element 15can be dimensioned such that in the installed state clamping forcesF_(K) are exerted by the wire arrays 7, 9 onto the intermediatelydisposed heat accumulator element 15, as shown in FIG. 4. In this casethe wires of the wire arrays 7, 9 should be bent apart in an elasticallyresilient manner when the heat accumulator element 15 is installed inthe condenser 3 so that the strip-shaped heat accumulator element 15 canbe introduced into the installation interspace 13.

FIG. 5 shows in a second exemplary embodiment a condenser 3 provided onthe rear side of the refrigerator and having a heat accumulator element15. In contrast to the preceding figures, the heat accumulator element15 according to FIG. 5 is oriented in the vertical direction as well asroughly at right angles with respect to the horizontal condenser tubesections 5. In this case the strip-shaped heat accumulator element 15 isthreaded through the tube sections 5 in roughly a meandering shape inthe region of the laterally outer tube bends 6. In this way theinstallation interspace 13 between the horizontal, straight tubesections 5 can remain completely free, thereby enabling free airconvection between the straight tube sections 5 of the condenser 3without any adverse effect due to the heat accumulator element 15.

The left side of the condenser 3 not shown in FIG. 5 is provided in thesame way with a vertically arranged, strip-shaped heat accumulatorelement 15. Arranged between the two lateral heat accumulator elements15 are the wire arrays 7, 9 which increase the size of the surface areaof the condenser 3 without any adverse effect caused byinward-protruding heat accumulator elements.

The upper end 21 of the heat accumulator element 15 shown in FIG. 5 isfolded in the manner of a loop around the top-side tube section 5 of thecondenser 3 and fixed in place by means of an indicated fastening pin23.

FIG. 6 likewise shows a heat accumulator element 15 arranged on the edgeside of the condenser 3 in a modification of the exemplary embodimentaccording to FIG. 5. As in FIG. 5, here, too, only the right rear sideof the refrigerator is shown. The left side not shown is essentiallyembodied mirror-symmetrically likewise with an edge-side heataccumulator element 15. In contrast to FIG. 5, the heat accumulatorelement 15 in FIG. 6 is a rigid, roughly U-shaped hollow profile part.The strip-shaped hollow profile part is mounted with its open side inthe manner of a cover onto the edge-side tube bends 6 of the condenser3. The cavity delimited by the U limbs 24 of the heat accumulatorelement 15 is dimensioned such that the condenser tube bends 6 can beinserted into the heat accumulator element 15, with a clamping tensionbeing built up in the process. As in FIG. 5, in FIG. 6 the coolingstructures 7, 9 are also provided between the two laterally insertedheat accumulator elements 15.

In contrast to the preceding exemplary embodiments, FIG. 7 shows arefrigerator having a forced-ventilation condenser 3 together with acompressor 25 as well as a separate fan 27 arranged between thecondenser 3 and the compressor 25.

The device combination shown in FIG. 7, consisting of condenser 3, fan27 and compressor 25, is arranged in a machine space 28 of therefrigerator. Said space is embodied in a rear section of therefrigerator close to the floor.

During operation the fan 27 generates a cooling air flow I which ispulled through the condenser 3. In this case the condenser is a finnedheat exchanger. In order to avoid a leakage flow past the condenser 3,the condenser 3 is arranged in an airtight cooling air duct 30.

In FIG. 7, the cooling air duct 30 is delimited by the upper ceilingwall of the machine space 28 as well as by a bottom base plate 32 onwhich the device combination stands. In the installation depth directionx, the cooling air duct 30 is delimited by two edge-side heataccumulator elements 15 arranged in an upright position. These aremounted analogously to FIG. 6 laterally onto the edge-side condensertube bends 6 and, acting in a dual function, delimit the cooling airduct 30 in an airtight manner.

Toward that end each of the heat accumulator elements 15 can have, onits side facing the condenser, recesses into which the tube bends 6 canproject in a positive-locking manner.

LIST OF REFERENCE SIGNS

-   1 Refrigerator-   3 Condenser-   5 Condenser-tube sections-   6 Tube bends of the condenser 3-   7, 9 Cooling structures-   11 Connecting points-   13 Installation interspace-   15 Heat accumulator element-   17 Air flow gap-   19 Retaining elements-   21 Upper end of the heat accumulator element 15-   23 Fastening pin-   24 U limbs of the heat accumulator element 15-   25 Compressor-   27 Fan-   28 Machine space-   30 Cooling air duct-   32 Base plate-   I Cooling air flow-   x Installation depth direction-   F_(K) Clamping forces

1-15. (canceled)
 16. A refrigerator, comprising: a refrigeratingcircuit; a condenser connected into the refrigerating circuit andconstructed in the form of a heat exchanger having tube sections forducting a refrigerant; and at least one heat accumulator elementinserted into an installation interspace between the tube sections ofthe condenser, said heat accumulator element being arranged inspaced-apart relationship to the tube sections of the condenser by atleast one predefined air flow gap.
 17. The refrigerator of claim 16,constructed in the form of a domestic refrigerator.
 18. The refrigeratorof claim 16, wherein the condenser has at least one member selected fromthe group consisting of a front-side cooling structure and a rear-sidecooling structure, said member delimiting the installation interspacetogether with the tube sections of the condenser.
 19. The refrigeratorof claim 16, wherein the condenser has a wire array delimiting theinstallation interspace together with the tube sections of thecondenser.
 20. The refrigerator of claim 16, wherein the heataccumulator element is arranged contactlessly between two neighboringtube sections.
 21. The refrigerator of claim 16, wherein the heataccumulator element is arranged contactlessly roughly centrally betweentwo neighboring tube sections.
 22. The refrigerator of claim 16, furthercomprising at least one retaining element provided in the installationinterspace between the tube sections of the condenser for retaining theheat accumulator element.
 23. The refrigerator of claim 22, wherein theretaining element is formed on at least one member of the condenserselected from the group consisting of a front cooling structure and arear cooling structure.
 24. The refrigerator of claim 23, wherein theretaining element is a retaining wire.
 25. The refrigerator of claim 16,wherein the heat accumulator element is fixedly clamped in theinstallation interspace between front and rear cooling structures of thecondenser.
 26. The refrigerator of claim 16, wherein the tube sectionsare straight tube sections, said condenser including tube bends torespectively connect the straight tube sections, said at least one heataccumulator element interactively cooperating with the condenser andarranged on an edge side in a region of the tube bends of the condenser.27. The refrigerator of claim 26, further comprising two of said heataccumulator element respectively arranged on opposite edge sides of thecondenser and extending along the condenser edge sides.
 28. Therefrigerator of claim 27, wherein the heat accumulator elements arearranged to leave free installation interspaces between the tubesections of the condenser.
 29. The refrigerator of claim 27, wherein theedge sides extend vertically.
 30. The refrigerator of claim 27, whereinthe condenser has at least one member selected from the group consistingof a front cooling structure and a rear cooling structure, said memberbeing arranged between the two heat accumulator elements.
 31. Therefrigerator of claim 16, wherein the heat accumulator element isthreaded through the tube sections in a meandering shape and orientedroughly at right angles with respect to the tube sections.
 32. Therefrigerator of claim 26, wherein the heat accumulator element has atleast one recess into which a tube bend of the condenser projects. 33.The refrigerator of claim 26, wherein the heat accumulator element is aroughly U-shaped hollow profile part having a cavity into which the tubebends of the condenser project.
 34. The refrigerator of claim 16,further comprising a fan for forced ventilation of the condenser, saidcondenser being arranged in a cooling air duct which is at least partlydelimited by the at least one heat accumulator element.
 35. Therefrigerator of claim 34, further comprising a plurality of said heataccumulator element, said heat accumulator elements being constructed ascooling air duct sidewalls between which the condenser is arranged. 36.The refrigerator of claim 16, wherein the heat accumulator element has amaterial which changes its aggregate state upon absorbing heat given offby the condenser in a refrigeration process.
 37. A refrigerator,comprising: a refrigerating circuit; a condenser connected into therefrigerating circuit and constructed in the form of a heat exchangerhaving straight tube sections and tube bends to respectively connect thestraight tube sections; and at least one heat accumulator elementinteractively cooperating with the condenser and arranged on an edgeside in a region of the tube bends of the condenser.
 38. Therefrigerator of claim 37, further comprising two of said heataccumulator element respectively arranged on opposite edge sides of thecondenser and extending along the condenser edge sides.
 39. Therefrigerator of claim 38, wherein the heat accumulator elements arearranged to leave free installation interspaces between the tubesections of the condenser.
 40. The refrigerator of claim 38, wherein theedge sides extend vertically.
 41. The refrigerator of claim 38, whereinthe condenser has at least one member selected from the group consistingof a front cooling structure and a rear cooling structure, said memberbeing arranged between the two heat accumulator elements.
 42. Therefrigerator of claim 37, wherein the heat accumulator element isthreaded through the tube sections in a meandering shape and orientedroughly at right angles with respect to the tube sections.
 43. Therefrigerator of claim 37, wherein the heat accumulator element has atleast one recess into which a tube bend of the condenser projects. 44.The refrigerator of claim 37, wherein the heat accumulator element is aroughly U-shaped hollow profile part having a cavity into which the tubebends of the condenser project.
 45. A refrigerator, comprising: arefrigerating circuit; a condenser connected into the refrigeratingcircuit and arranged in a cooling air duct; a fan for forced ventilationof the condenser; and at least one heat accumulator element at leastpartly delimiting the cooling air duct.
 46. The refrigerator of claim45, further comprising a plurality of said heat accumulator element,said heat accumulator elements being constructed as cooling air ductsidewalls between which the condenser is arranged.